Sound-reproducing device



1443mm. N. MENDEZ.

SOUND REPRODUGING DEVICE. FILED JAN-23,1919- Patented dun, 1 93, T923,

SGUND-REPRODUCING- DEVICE.

Application filed. January 2a, 1919. fSerial no. eraser.

To all whom it may concern Be it known Iliad? I, Nroanon Mnrmnz, a

citizen of the Argentine hepublic, and resident of lielgrano, Huenos :riires, Argentina, have invente certain new andusetul improvements in Sourid-Reproducing Devices, of which the following 's a Specification.

This invention refers to improvements in talking machines or sound reproducing devices, and more particularly to a new and improved membrane or diaphragm which is applicable to any machine or apparatus of the above mentioned.nature.

In order that any sound may be transformed into sensation, that is to say audibly reproduced, it suificient to produce a special vibratory movement in the sonorous bodies, a principle of acoustics which is of general application in all such instruments.

This invention is the result of much study of the scientific basis oi'physical acoustics, observing the causes which act upon sonorous bodies in vibration, the transmission of. the vibration in a certain direction and the elasticity of the vibration. medium, as well as the reflection of sound together with'all the phenomena of echo and resonance.

For example, in order to obtain a perfect transmission of sounds and more especially the exact reproduction of musical eit'ects, it

is necessary to take into consideration. all the rules of acoustics, the scientific basis of themusical art and ot phonation.

The principal object of this invention is to provide a device for the purpose of attaining with the least possible number of mechanical elements, the exact reproduction and transmission of the voice or of other sounds free from all extraneous influence which mightinjure the purity of the timbre and olearncss o'l enunciation.

The above described object of the invention may be subdivided as follows: (1.) To providean elastic material which on being caused to vibrate will transmit its vibradiminish the sonorous qualities of the instrument and at the same time produce a jumping effect, or a greater number of vibrations, which if not deadened will give an imperfect emission; (3) To provide an easy and rapid means of placing and fastening or removing the needle by means of a mechanism or device which secures a perfect alignment and locking effect by one-fifth of a turn, fixing the needle by means of a screw so that it may be held firmly and rigidly in order to eiiect the positive and smooth movements imparted to it by the track upon the disc, and to transmit the same by means of; the transmitter post to the membrane or diaphragm proper. There is no known mechanism hitherto used by which all of these objects may be perfectly obtained, since in all of them the entire periphery of the needle is not held by the usual means of a set screw pressing against one side only of the needle; (4-) To insure a greater facility in the assembling or dismounting of the transmitting mechanism on account of its reduced number of pieces, the security oi? the joints, the manner of fixing .the sound conductor tube or arm to the trumpet, the special link connecting the membrane with the medic-holder which serves to regulate by means of a spring the complete vibration of the part extending from the needle-holder to the centre of the diaphragm; and other characteristics which will be set forth more fully hereinafter and which in combination amply satisfy the objects of the invention in a scientific and satisfactory form with all the conveniences of simplicity, economy and artistic and phonetic utility.

Numerous apparatus or devices or" this nature are known in the art, in which the esthetic part or outward appearance has been success'tuily perfected; there are also devices such as uniform speed motors for moving the discs, and many systems or kinds of needles, either of steel or vegetable substances There are also the existing inventions having reference to the augmenting; devices or trumpets for the better application of the sounds emitted, but in reality, in none of these apparatus or devices has theebsolute purity or ita-ithiul reproduction oi sou'ndbeen achieved, in so far as their characteristic quality is concerned.

I The advantage of the hereindesoribed device over all other known vibrating devices consists in the simplicity of the means of connection between the needleholder and the reproducing diaphragm which is the basis or this result, in a vibration device which is smooth and strong at the same time without ever being disagreeably acute, reproducing exactly the voice or sound recorded upon the disc with all of its characteristic tone qualities and without excessive vibrations productive of disagreeable sharp ell'ccts nor the equally objectionable contrary effect oi dullness or lack of clearness.

The materials employed'may for the most part be varied according to their local avail ability and price; but the diaphragm proper or vibrating medium according to my inven tion is of celluloid or the like, which I have found to be far superior to the usual mica or any other substances for the exact reproduction of tone qualities. I have also found by experiments that by giving the diaphragm, which must bevery thin, a series of concentric undulations or corrugations, which the nature of celluloid facilitates by a stamping or pressing process, a great improvement is noted in the smoothness and uniformness of the tone, which however is never harsh or disagreeable, however voluminous it may be.

In a word, the special celluloid membrane or diaphragm which is the principal object or" this invention, is superior to all others on account of its mechanical properties which meet the requirements of acoustic laws, as well as its solidity and simple construction and conditions of transmissibility due to the special combination of connections between the needle-holder and the diaphragm, and to the characteristics of the latter.

In the accompanying drawings, Fig. i is a front view of my improved undulated celluloid diaphragm with its housing and accessories; Fig. 2 is a side view of the same; Fig. 3 is a cross section of the same; Fig. et is a side view of the rear part of the same; Fig. 5 is a front view of the same part; Fig. 6 is a side view of the sound transmitting mechanism with its rod or post (f) and spring (a); Fig. 7 is a front view of the celluloid diaphragm proper with concentric circular undulations; Fig. 8 is a plain diaphragm without undulations; and Figs. 9 and 10 are details to an enlarged scale of the connections between the diaphragm housing and the transmitting vibratory mechanism.

In the said figures the diaphragm housmg as seen in Fig. 1 is formed by the piece (a) which is the front part of the housing and'is united to the rear part (b) of the same by means of a threaded intermediate part (0) in such a manner that the pieces (a) and (b) are hermetically united; and at the union of these two pieces ((1 and (/1) there is a small screw (1') to prevent the movement of the said pieces.

(in the inside of the diaphragm housing there is a convenient cavity where two rubber washers (q) are placed between which is held the celluloid diaphragm (d) or (m) which are respectively smooth and provided with circular undulations in order to make the sound or voice transmission smooth and firm.

Having thus described the diaphragm housing composed of the pieces ((1.) and (6) between which is rigidly held the diaphragm proper, let us pass now to describe the connections of the needle-holder.

The letter (f) indicates the sound trans mitter rod or post, the upper end of which is fastened to the diaphragm (d) by means of a small screw The post which extends from the centre of the diaphragm to the part (5 unites it to the needle-holder (j) from one side oi the lower part of the diaphragm housing there projects a pair 01. spaced lugs (2?) each of which is provided with a downwardly extending blade (t), these blades fit into the grooves of the part 1), the joint being controlled by a spiral retraetile spring (n) extending from the prolongation of the needle-holder to a head a which is attached to the spring being fitted on and between the lugs thus completing the imaeiiilily of the device, without the necessity oi employing tools.

Inside of the needle-holder the needle (2') is secured and firmly adjusted by the outer threaded part thereof which engages the inner thread of the setting nut (/1).

The sound transmitter post (f), provided with a small screw which unites it to the centre of the diaphragm proper, extends to the part (g) and from the centre of the said part extends the needle-holder (j) which consists of a small turned and threaded piece perforated through its longitudinal centre, the perforation having a diametre of about 1-} millimetres and 9 millimetres of depth, being tapered toward the lower end so that the needle may be introduced therein. For closing the same upon the needle in order to hold the latter tightly on all sides and in. perfect alignment. with the holder, the needle-holder is divided in four longitudinal. parts by two crossed grooves at right angles to each other and is provided with an adjusting nut (h), which by one-fifth of a turn acts upon the conical threaded part which it presses inwardly against the needle, thus effecting quickly and firmly the locking of the needle in its position by a uniform pressure against its entire periphery, instead of the. usual side pressure in a single direct-ion by a common set screw.

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The back piece (b) 01'' the diaphragm housing is provided at its central part with a sleeve (is) which by means of a pin (Z) is adjusted to the groove of the elbow which is jointed to the sound tube or arm of the apparatus in the usual manner. Thus the complete diaphragm and housing are secured to the sound magnifying trumpet.

The letter (m) represents a plain celluloid diaphragm which may be substituted for the concentrically undulated diaphragm (d).

As will be seen from the above description, the principal characteristic of the invention consists in the use of the celluloid diaphragm, by which tone qualities are more faithfully reproduced than by any other known material from which diaphragms have been made, and although the added fact of the concentric circular undulations still further increases the excellence and exactness of the tone quality reproduction, the plain celluloid diaphragm by itself constitutes a marked improvement over all others heretofore known, and I therefore claim the use of celluloid for the making of diaphragms for talking machines or sound reproducing devices in general.

In the improved connections which I use in conjunction with the celluloid diaphragm, a greater smoothness of sound is obtained by the improved simplicity of construction and especially by the spring (a) which also serves to spring into its vibratory position the needle carrying mechanism without the use of tools, and to hold the same flexibly in said position in a very efficient and delicately balanced manner. A distinct mechanical advantage is also obtained by means of the needle setting device consisting of the cross-split threaded holder (3') and set nut which insure a perfect alignment of the needle and holder and facilitate the rapid introduction and removal of the needle.

When celluloid is mentioned in the above description and in the appended claims, it should be understood that any similar material is included, regardless of its commercial name. It will also be understood that small details of construction such as usually occur to persons skilled in the art, may be varied and introduced in this improved apparatus without thereby departing from the spirit of the invention as expressed in the following claims.

Having thus described my invention what I claim and desire to protect by Letters Patent of the United States is In a talking machine, a sound box having a pair of spaced lugs at one side, each provided on the under side with a blade, a diaphragm in the sound box, a sound transmitter rod having one end connected to the diaphragm and the other end provided with an angular arm having grooves to receive the ends of said blades, a needle, a needle holder extending through said arm and mounted in said attaching means, and a coiled retractile spring having one end at tached to the needle holder and being provided at the other end with a head which is V detachably mounted on and between the spaced lugs.

Signed at the United States consulategeneral at Buenes Aires, Argentine Republic, this 18th day of December, A. D. 1918.

NICANOR MEND-EZ.

Witnesses:

Vroron W. ANTMOY, N. W. HUNTINGTON. 

